Abstract:Canopy gap characteristics and spatial distribution play an important role in forest structure optimization and function restoration. Based on airborne laser scanning data and field evidence across sites, descriptive statistics were used to identify and examine gap characteristics. Ripley’s K function analysis was applied to test gap spatial patterns at a range of scales, and spatial point pattern analysis was used to quantify the relative importance of specific influences on patterns of gap occurrence. The results revealed that the average gap size was 78.9m2 and that 12.8 gaps occurred per hectare. In addition to more gaps, the mean gap size was smaller and the shape was more complex in the secondary forest site than in two managed sites. Large differences in gap characteristics were observed among natural disturbances and artificial gap. Gaps generally showed a clustered distribution at large scales, whereas spatial patterns varied with gap damage types at different sites. The occurrence of gaps was strongly related to slope and topographic position at the secondary forest site, whereas slope, stem density, and human accessibility (proximity to pathways) were the most important factors affecting gap occurrence at the managed sites. The purpose was to clarify the mechanism of forest gap disturbance and provide methodological reference and technical support for forest management to adapt to climate change.